AS cracks appeared in Oxford University's Clarendon Building, library staff became worried the historic structure was sinking.

Toby Kirtley, estate projects officer for Oxford University Library Services, outside the Clarendon Building, in Broad Street, Oxford

Once the rumour was repeated, librarians were convinced that the Broad Street building's foundations were slowly crumbling and had subsided 11cm in the past 11 years.

But tests carried out by a structural engineer revealed no significant movement and subsidence of the Grade I-listed building, built on the site of the old city ditch, has been ruled out.

A total of 45 staff have now been relocated so that a £1m refurbishment programme can begin to restore the building, designed by Nicholas Hawksmoor to house the university's printing press.

It is now home to Bodleian Library staff, but for the next 12 months they will be working at offices on the city's Osney Mead industrial estate.

"We were aware of the rumours about the building sinking," said Toby Kirtley, 40, estate projects officer for Oxford University Library Services.

"We called in structural engineers last year as part of the design process for this project and made them aware of the rumours.

"They carried out an inspection and did not find any problems with subsidence.

"It was an apocryphal tale and I would love to know where it started.

"There are some cracks in the plaster on the ceilings and walls inside the building, but they did not appear recently and you would expect some gentle movement over 300 years."

Inside, the building is being refurbished at a cost of £1m to accommodate the directorate of Oxford University Library Services -- which is transferring from the old Bodleian building -- and existing personnel, accounts and admissions staff from the Bodleian.

Partition walls that divide Hawksmoor's original design are being removed and replaced in some areas with glass.

Repairs to stonework, casement windows, roof timbers and high-level plaster will also be completed.

The £1m project follows last year's work at the Sheldonian Theatre to carry out £1m of ceiling repairs. The 17th-century building reopened in time for the Christmas season.

Mr Kirtley added: "The Christopher Wren-built Sheldonian Theatre is slightly older than the Clarendon Building, but there's a connection because the Sheldonian once housed the university printing press."